2020 presidential candidate and former Vice President Joe Biden this weekend apologized for the "pain and misconception" caused by his recent remarks about working with bigoted segregationist senators during his time on Capitol Hill. The Democratic frontrunner also invoked his former boss, President Barack Obama, in defending his civil rights record.

"Everything they stood for offended me. They represented everything that I ran against," Biden said during a campaign event in Sumter, South Carolina, on Saturday. The 76-year-old candidate was referring to a pair of openly racist former Senate colleagues that Biden had recently boasted of having a civil working relationship with.

He continued: "I do believe we have work to do, even with those who we find repugnant, to make our system of government to work for all of us. I believe then and I believe now, and I know it can be done without compromising on our principles."

"Was I wrong a few weeks ago to somehow give the impression to people that I was praising those men who I successfully opposed time and again?" the former vice president asked, before answering his own question: "Yes I was, I regret it. I'm sorry for the pain and misconception I may have caused anybody."

"But should that misstep define 50 years of my record for fighting for civil rights, racial justice in this country? I hope not, I don't think so. That just isn't an honest assessment of my record," he added.

Biden's apology came more than a week after he was called out by Senators Kamala Harris and Cory Booker for mentioning his past work with two racist Democrats, Senators James O. Eastland of Mississippi and Herman Talmadge of Georgia, who both advocated for segregation.

During the first 2020 Democratic presidential primary debate last week, Harris told Biden: "I do not believe you are a racist and I agree with you when you commit yourself to the importance of finding common ground. But I also believe, and it's personal and I was actually very — it was hurtful to hear you talk about the reputations of two United States senators who built their reputations and career on the segregation of race in this country."

In taking on critics who have dug into his long history in public life, Biden on Saturday invoked Obama's faith in him as a running mate to defend his civil rights record.

"America in 2019 is a very different place than the America of the 1970s. And that's a good thing," Biden said, according to a transcript circulated by his campaign ahead of his speech. "I've witnessed an incredible amount of change in this nation and I've worked to make that change happen. And yes — I've changed also."

"It was the honor of a lifetime to serve with a man who was a great President, a historic figure, and most important to me — a friend," Biden reportedly added. "I was vetted by him and selected by him. I will take his judgment of my record, my character, and my ability to handle the job over anyone else's."

Obama, who served as America's first black president, selected Biden to be his vice in 2008.

Former Vice President and 2020 presidential candidate Joe Biden speaks during a campaign event on July 4, 2019 in Marshalltown, Iowa. Biden on Saturday apologized for praising segregationist senators at a campaign event in Sumter, South Carolina.Joshua Lott/Getty